Oil is contained in oil crops, any kind of vegetable oil is extracted from oil crops, and mostly extracted vegetable oil is not suitable for direct consumption, it should be refined for eating, different extraction and refining process determines the product quality. Let's take a look at what are the different grape seed oil extraction method and refining process, what they have and their different features.
- Solvent Extraction
Grape seed after drying, crushing, humidify, use organic solvent for spraying and soaking, extract grape seed oil from the grape seeds, and then get the crude grape seed oil isolated from mixed oil.
Solvent extraction yield efficiency is higher, extraction is more complete, the solvent can be recycled, easy to operate, cost is relatively low; however, in the process of solvent recovery, it is easy to make unsaturated fatty acid decomposition, which makes the saponification value of crude oil high, and the products of solvent residues.
- Press Extraction
Grape seeds are derived from grape juicing after drying and peeling, then remove impurities to break up, after softening step finally into the oil press to get crude grape seed oil.
Press extraction is simple, easy to realize industrialized production, no chemical pollution, and easy separation; however, it has other shortcomings such as hard grape seed nucleus, low yield efficiency, high residual oil content in slag, large energy consumption and easy to make the machine shaft fracture etc.
- Supercritical CO2 Extraction
Grape seed goes into extraction kettle after drying, crushing, carbon dioxide turns into supercritical fluid which has gas diffusion and liquid density after high-pressure pump pressing, heat exchanger heating, it goes into the separation column through extraction kettle after leaching grape seed oil, grape seed oil and carbon dioxide separate after decompression and heating.
Supercritical CO2 extraction method can low temperature operation, avoids the oxidation of unsaturated fatty acid decomposition, it has advantages of high extraction yield, low energy consumption and no residual solvent, it is a new extraction technology developed in recent years which has been widely used in food, medicine, chemical industry and other fields.
Grape Seed Oil Refining
Both solvent and press method of extraction of grape seed oil need refining processing because it contains pigment, fat-soluble magazine etc dad for grape seed oil storage and consumption. At present, grape seeds oil refining process is as follows: crude grape seed oil filter, degumming, alkali refining, washing, drying, decoloring, deodorization, finally get the finished product of grape seed oil.
Advantages of Grape Seed Oil
The unsaturated fatty acids in grape seed oil accounted for 90% of the total fatty acid content, more than 75% of unsaturated fatty acid is linoleic acid ( linoleic acid is the main substance for body synthesis twenty four carbon, it prevents thrombosis, dilate blood vessels. So, grape seed oil is not only have the function of the lower serum cholesterol, but also can nutrition nerve cells, adjust plant nerve function at the same time), grape seed oil is one of the highest linoleic acid content vegetable oil (peanut oil linoleic acid only contains about 40%).
Grape seed oil contains a large number of fat-soluble vitamins A, D, E and K, content reach VE35.95, VK29.41, VA8.06, VD4.03, VP0.94 mg / 100 grams of oil, a tablespoon of grape seed oil is equivalent to all the vitamin E a person need one day.
Characteristics of Grape Seed Oil
Because the high linoleic acid content in grape seed oil, as a cooking oil has excellent properties, thermal stability, smoke point as high as 248 degrees, high temperature cooking do not pollute the environment, it is environmental protection, health edible oil. Cooking with only 1/2, 1/3 of grape seed oil can achieve the same cook effect of other oil, it is very economic also avoid too much fat intake, have attained renown by gourmet chef and housewife.